Download Impacts of climate change on coastal erosion

MARINE CLIMATE CHANGE IMPACTS PARTNERSHIP: SCIENCE REVIEW
MCCIP Science Review 2013: 71-86
Submitted June 2013
Published online 28 November 2013
doi:10.14465/2013.arc09.071-086
Impacts of climate change on coastal erosion
Gerd Masselink and Paul Russell
School of Marine Science and Engineering, Plymouth University, Plymouth, PL4 8AA, UK
EXECUTIVE SUMMARY
A large proportion of the coastline of the UK and Ireland is currently suffering from erosion (17% in the UK; 20% in
Ireland) and of the 3,700 km coastline of England and Wales 28% is experiencing erosion greater than 10 cm per year.
The natural response of coastal systems to sea-level rise is to migrate landward, through erosion of the lower part of
the nearshore profile and deposition on the upper part. The roll-over model is applicable to estuaries, barriers and
tidal flats. Rocky coasts are erosional coasts by their nature and retreat even under stable sea-level conditions. Where
the coast is protected by engineering structures, coasts are generally experiencing a steepening of the intertidal profile.
Coastal response to sea-level rise is strongly determined by site-specific factors and usually it is these factors that
determine the coastal response, rather than a global change in sea level or a regional change in wave climate. Any
predictions of general coastal response due to climate change are therefore rather meaningless and will have a low
confidence. However, if a detailed study is conducted and long-term coastal change data are available, then local or
regional predictions of coastal response to climate change can have medium confidence.
In the absence of a clear understanding of the coastal-change processes, and therefore a reliable predictive tool, the
default position is to assume that present-day coastal change will persist; however, it is very likely that currently
eroding stretches of coast will experience increased erosion rates due to sea-level rise.
The coastal management strategy (e.g., hard coastal defences, beach nourishment, managed realignment) is also a
key aspect for determining the long-term response of the coast to climate change effects, including sea-level rise.
Managed realignment is likely to increase in the future as a key management strategy and although this will result in
increased local erosion rates, the enhanced erosion may benefit other sections of coast by reducing erosion or even
causing accretion. Adaptation is emerging as the key coastal management paradigm to cope with coastal erosion.
INTRODUCTION
Coastal erosion is widespread in the UK and the Foresight
Flood and Coastal Defence Project estimates current damage
due to coastal erosion at £15 million per year, which in
the worst case may rise to £126 million per year by 2080
(Foresight, 2004). An extreme illustration of erosion risk is
shown in Figure 1 for the case of the village of Happisburgh
in Norfolk. Here, the coastline position has been artificially
maintained for decades using hard coastal defence structures
and their part removal has resulted in rapid coastal erosion
(e.g., Poulton et al., 2006). Sea-level rise is a key factor in
causing coastal erosion and concerns about erosion risk have
mounted in light of increased rates of sea-level rise predicted
due to climate change.
Responsibility for the management of coastal erosion in
the UK has recently been passed on from the Department
of Food and Rural Affairs (DEFRA) to the Environment
Agency (EA) (together with coastal councils). At a national
level, the Making Space for Water initiative still provides
important strategic guidance for dealing with coastal
(and river) management. The key aspect of the strategy is
that sustainable development should be firmly rooted in
all flood risk management and coastal erosion decisions
and operations (http://archive.defra.gov.uk/environment/
flooding/documents/policy/strategy/strategy-response1.
pdf). At a local and regional level, strategic guidance for
coastal management is provided through (non-statutory)
Shoreline Management Plans (SMPs). The plans provide a
large-scale assessment of the risks associated with coastal
processes and present a long term policy framework to reduce
these risks to people and the developed, historic and natural
environment in a sustainable manner (http://archive.defra.
gov.uk/environment/flooding/documents/policy/guidance/
smpguide/smpgvol1.pdf).
The Making Space for Water philosophy has been fully
incorporated into the second generation SMPs, which
increasingly consider managed realignment as the preferred
management strategy, leading to controversial SMPs (e.g.
SMP for North Norfolk; Fletcher, in press).
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G. MASSELINK AND P. RUSSELL
Figure 1: Coastal erosion at Happisburgh, Norfolk, from 1993 to 2003. It should be pointed out that the erosion recorded in these
photographs is extreme and to a large degree the result of the removal of coastal defences.
This review will first provide an overview of current erosion
rates in the UK (Section 1) and what is likely to happen in
the future (Section 2). Contrary to common beliefs, coastal
erosion is not solely and simply linked to sea-level rise, and
the key message of this report is that that coastal erosion is
a complex process that has a variety of causes, with rising
sea level being only one of them. Most importantly, whereas
climate change and relative sea-level rise are global and
regional phenomena, respectively, coastal erosion is a local
process. In this respect, this report is rather different from
other MCCIP reports.
Importantly, erosion of one stretch of coast is likely to cause
accretion elsewhere – sediment is generally not lost from the
coastal system. This notion has recently been demonstrated
in a study by Montreuil and Bullard (2012) on the east coast
of England. Here, the rapid erosion of the Holderness cliffs
to the north of the Humber is, in part, counterbalanced
with accretion on beaches along the north Lincolnshire
coast to the south of the Humber. The amount of accretion
in Lincolnshire corresponds to around 29% of the volume
of sediment eroded from Holderness, and increased cliff
recession rates of the Holderness coast as a result of sealevel rise may even lead to increased accretion and shoreline
progradation along the north Lincolnshire coast (the
remaining 71% of eroded sediment ends up in the Humber
estuary, including the ebb tidal delta and Spurn Head spit
system, or is transported furthered afield, perhaps even as far
as the Dutch Wadden Sea).
Due to the complex and multi-facetted nature of coastal
erosion, most of this review is concerned with describing
the most relevant processes involved with coastal erosion
and discussing how these processes affect different types of
coastal environments. At the end of the report, management
strategies that address coastal erosion problems are briefly
discussed .
1. WHAT IS ALREADY HAPPENING?
According to the most recent European-wide study into
coastal geomorphology and erosion (EUROSION, 2004), the
UK coastline is 17,381 km long, of which 3,008 km (17.3%)
are currently experiencing erosion (Table 1). The coastline of
England is most affected, with 29.8% of its coastline suffering
from erosion. The coastline of England is also the most
protected with 45.6% of its length lined with coastal defence
works (seawalls, groins) or fronted by artificial beaches.
According to the same EU report, Ireland has 4,578 km of
coastline, of which 19.9% is eroding and 7.6% is protected.
The Foresight Flood and Coastal Defence Project provides
estimates of present and future (next 100 years) coastal
erosion rates for the coast of England and Wales (Foresight,
2004). According to their analysis, 28% of the coast is
experiencing erosion rates in excess of 10 cm yr-1 (Evans et al.,
2004; Burgess et al., 2007). A large proportion of the coastline
is held in position artificially, however, and a more realistic
estimate of potential erosion is that 67% of the coastline is
under threat (Futurecoast, 2002). More recently, the National
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IMPACTS OF CLIMATE CHANGE ON COASTAL EROSION
73
Table 1: Coastal erosion and protection in the UK (EUROSION, 2004). Islands with a surface area smaller than 1 km and inland
shores (estuaries, fjords, fjards, bays, lagoons) where the mouth is less than 1 km wide are not included in the analysis.
2
Region
Coast length
Coast length that
is eroding
Coast length
that is eroding
Coast length with
defence works
and artificial
beaches
Coast length with
defence works and
artificial beaches
km
km
%
km
%
Northeast England
297
80
27.0
111
37.4
Northwest England
659
122
18.5
329
49.9
Yorkshire and
Humber
361
203
56.2
156
43.2
East Midlands
234
21
9.0
234
99.8
East England
555
168
30.3
382
68.9
Southeast England
788
244
31.0
429
54.4
Southwest England
1379
437
31.7
306
22.2
England
4273
1275
29.8
1947
45.6
Wales
1498
346
23.1
415
27.7
Scotland
11154
1298
11.6
733
6.6
456
89
19.5
90
19.7
UK
17381
3008
17.3
3185
18.3
Ireland
4578
912
19.9
349
7.6
Northern Ireland
Coastal Erosion Risk Mapping project (Rogers et al., 2008)
has suggested that 42% of the coast of England and Wales is
at risk from erosion, of which 82% is undefended. However,
this project is only concerned with cliffed coastlines and
does not consider coastal floodplains, beaches, barriers and
intertidal areas.
Where the coast is protected by engineering structures, the
rising sea level results in a steepening of the intertidal profile,
known as coastal squeeze. According to Taylor et al. (2004)
almost two-thirds of intertidal profiles in England and
Wales have steepened over the past hundred years; however,
a re-evaluation of these results by Dornbush et al. (2008),
pertaining to the south-east coast of England, suggests that
steepening is less common.
2. WHAT COULD HAPPEN?
The two main consequences of climate change that have an
impact on coastal erosion and coastal geomorphology are
sea-level rise and changes to the wave climate (storminess
and prevailing wave direction). The global rate of sea-level
rise estimated from (satellite) altimetry data over the 15-year
period from 1993 to 2008 is 3.5 mm per year (Nicholls and
Cazenave, 2010). Most global sea-level data sets suggest that
the rate of sea-level rise is accelerating (Church and White,
2006; Rahmstorf et al., 2012, their Figure 1); however, not all
coastal locations seem to conform to this accelerating trend.
For example, Haigh et al. (2011) found that the current rate
of sea-level rise at 16 sites along the English Channel over
the period 1993-2008 was considerably higher than that
averaged over the complete data records, but was within the
envelope of observed change when compared with other
15-year periods since 1900. In other words, there have been
several periods during the 20th Century that the rate of sealevel rise along the English Channel was similar to that at
present.
The Fourth Assessment Report of the Intergovernmental
Panel on Climate Change (IPCC AR4) predicts that the rise
in global sea-level by 2100 will be in the range of 18–38 to
26–59 cm, depending on the emissions scenario (Meehl et
al., 2007). In these projections, the potential contribution of
rapid changes to the Greenland and Antarctic ice sheets are
not included, and the IPCC suggested an upper limit to sealevel rise during the 21st century of 0.76 m that does take into
account ice sheet dynamics. Since 2007, sea-level science has
progressed significantly (e.g. studies of ice sheet dynamics
and interglacial periods), and, in particular, semi-empirical
model projections of sea-level rise have been developed.
These models use present relationships between temperature
and sea-level rise combined with climate-model projections
of future warming to give an alternative set of future sealevel predictions (Rahmstorf, 2007). Many of these studies
suggest that the upper end of the sea-level projections by
2100 could be significantly higher that the IPCC projections
(e.g. 0.75–1.90 m according to Vermeer and Rahmstorf, 2009;
0.72–1.60 m according to Grinsted et al., 2009). Following
their analysis of sea-level rise and its possible coastal impacts
given a ‘beyond 4oC world’, Nicholls et al. (2011) suggest a
pragmatic estimate of sea-level rise by 2100 between 0.5 and
2 m.
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G. MASSELINK AND P. RUSSELL
Specifically for the UK, the IPCC climate change projections
have recently been updated by UKCP09 using Met Office
predictions and the key elements of these for coastal erosion
can be summarised as follows (http://ukclimateprojections.
defra.gov.uk/):
• Relative sea-level rise: During the 21st century, relative
sea-level (i.e. change in sea-level relative to the level of the
land) in the UK is expected to rise by 30–50 cm by 2100,
depending on emissions scenario. Because of differences in
land-level changes due to the glacial isostatic adjustment
(GIA), the projected relative sea-level rise in south England
is larger than in north England and Scotland (Figure 2 and
3). A low-probability, high-impact range of sea-level rise
scenarios, called the H++ scenario, based on observations of
the past and plausible constraints on ice sheet dynamics was
also developed. The H++ sea-level rise estimate for the UK is
0.93–1.90 m by 2100.
• Storm surge levels: If the predicted sea-level rise is
disregarded, there seems to be only a very modest increase
in predicted storm surge levels due to increased storminess.
Some support for these predictions is provided by Haigh et
al. (2010) who showed that the increase in extreme sea-levels
during the 20th century in the English Channel could almost
wholly be attributed to sea-level rise.
• Wave climate: The primary basis of UKCP09 projections of
future wave conditions is the HadCM3 AOGCM (Atmosphere
Ocean Global Climate Model), with 3.75° by 2.5° horizontal
spatial resolution. Alternative variants of model parameters
were selected to create a ‘perturbed physics ensemble’ (PPE)
and the results were also compared to results from a set of
independent climate models (referred to as a multi-model
ensemble (MME)) to provide insight into uncertainties.
Overall, changes in the seasonal mean significant wave
height are modest, generally < 0.1 m. Some regions might
actually experience a reduction in wave height due to the
projected southward movement of the storm tracks (Lowe
et al., 2009). Changes in the maximum wave conditions are
more pronounced, and the most sensitive areas are Charting
Progress Regions 3 and 4 (Eastern English Channel, Western
English Channel) and the south coast of Ireland, where an
increase in the maximum significant wave height of 0.5–1 m
can be expected by the end of this century. No H++ scenario
has been developed yet for waves.
The Foresight project estimated future coastal erosion rates
and compared these to the benchmark present condition
(20–67 m erosion over 100 years). Depending on the
emissions scenario, the amount of erosion predicted to
occur over the next 100 years ranges between 82 and 175
m, with the most severe erosion occurring in the east of
England (Evans et al., 2004) due to the combination of
disequilibrium morphology (shoreline is out of equilibrium
with prevailing wave direction and present sea-level) and an
easily erodable coastline made of unconsolidated material
(mainly clays). Such national, or even regional, predictions of
coastal erosion are not very useful, however, because coastal
erosion is largely a local process and coastal recession rates
are spatially highly variable. Coastal scientists and managers
Figure 2: Relative sea-level change around the UK over the
21st century. The change combines the central estimate for the
medium emissions scenario and vertical land movement, and
relates to the period to 2095 (UKCP09).
Figure 3: Glacial Isostatic Adjustment (GIA) map of the vertical
land movement for the UK (UKCP09; Adapted from Bradley
et al., 2008). Note that there is some doubt with regards to
the relatively large rate of relative sea-level in the southwest of
England (Gehrels, 2006). The white circle represents the line of
zero vertical land movement.
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IMPACTS OF CLIMATE CHANGE ON COASTAL EROSION
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are aware of the importance of geographical variability
in coastal change; therefore, a Geographical Information
System (GIS) framework is usually adopted to quantify
current and projected coastal changes, and assess societal
risk of coastal erosion. Examples of such initiatives include
Esteves et al. (2008) at the local scale, Nicholls et al. (2008)
on the regional scale and Rogers et al. (2008) at the national
scale. The latter project is of particular relevance to coastal
managers, because it combines existing coastal recession
rates with a probabilistic method for assessing the hazard and
risk of coastal erosion (resulting from the Risk Assessment of
Coastal Erosion project; Halcrow, 2006) to determine coastal
erosion risk at the local scale 20, 50 and 100 years into the
future.
Predicting future coastal erosion rates remains problematic.
In the absence of a clear understanding of the coastal-change
processes, including past coastal change and causes of
coastal erosion, and therefore a reliable predictive tool, the
default position is to assume that present-day coastal change
will persist; however, it is very likely that currently eroding
stretches of coast will experience increased erosion rates due
to sea-level rise. Moreover, the removal of coastal defences,
which is likely to increase in response to anticipated and
enhanced uptake of the managed realignment coastal
management strategy (e.g., Happisburgh), will also increase
coastal erosion rates. Therefore, the proportion of eroding
coastlines, and the average coastal recession rates, in both
UK and Ireland are expected to increase in the future.
Factors involved with coastal erosion and geomorphology
It is tempting to attribute the coastal erosion in the UK to
rising sea level; however, this is a serious over-simplification,
as several other, often more important, processes are involved:
• Sea-level history: Coasts do not respond instantaneously
to changing sea-levels, but evolve over time scales ranging
from centuries to millennia. Present-day trends in shoreline
position (erosion/accretion) are therefore often better
explained in terms of the sea-level history, than contemporary
sea-level change. In this context, the sea-level history of the
last 10,000 years has been particularly influential. Figure
4 shows the sea level at 7,500 BP, when global mean sealevel was c. 15 m below present (Shennan et al., 2000), and
highlights the contrast between the east coast of England and
the rest of the UK and also Ireland. At this time, the coastline
of east England had a very different shape and was located
more than 10 km seaward of the present coastline. The
implication is that this coast is very young, and is unlikely
to have adjusted to present sea level. The erosion rates along
the east coast of England are amongst the largest in the UK.
For example, the Holderness coast has retreated by c. 4 km
over the last 2000 years and many villages, including Roman
settlements, have been lost to the sea (http://databases.
eucc-d.de/files/000164_EUROSION_Holderness_coast.pdf)
and along parts of the Norfolk coast there has been almost
200 m of recession since 1885 (Clayton, 1989). In both these
cases, the erosion has nothing to do with the present day sealevel rise, but is largely attributed to their sea-level history.
• Relative sea-level change: The effect of eustatic (global)
sea-level rise on the coastline in the UK and Ireland must
Figure 4: Coastal configuration of NW Europe 7,500 years BP
(Shennan et al., 2000)
be considered in combination with the changes in the land
level associated with glacio-isostatic effects, in particular
isostatic rebound of the formerly glaciated areas in the north,
and collapse of the forebulge of areas near the ice margin in
the south (Shennan and Horton, 2002; Figure 3). There is
considerable regional variation in the estimated relative sealevel change, with relative sea-level in the south rising faster
than in the north (Figure 2), and this will have a significant
effect on the coastal response. In this context it is of interest
that it has been suggested that, for the first time since the
last glaciation, the eustatic sea-level rise is now outpacing
isostatic rebound in Scotland (Rennie and Hansom, 2011),
although this has been subject to some debate (Dawson et al.,
2012; Rennie and Hansom, 2012).
• Geology: The geology exerts its control on coastal erosion
mainly through the resistance of the rocks to denudation
(Figure 5) and provides the explanation for the contrast
between the high-relief, mainly rocky coast of west England,
Wales, Scotland, Northern Ireland and Ireland, and the lowrelief, mainly unconsolidated coast of east England (Clayton
and Shamoon, 1998). Cliff erosion is controlled to a large
extent by rock strength, with typical cliff recession rates
in hard and soft rock of 0.1–1 cm yr-1 and 10–100 cm yr-1,
respectively. The configuration of many estuaries is also
largely controlled by the geology, because most are drowned
river systems (Prandle, 2006). In addition, geology can
also play a major role in influencing the morphology and
dynamics of sandy beaches, especially in Ireland (Jackson et
al., 2005) and the south-west of England (Scott et al., 2011).
• Sediments: During deglaciation, large quantities of
sediments, comprising the full spectrum of sediment sizes
from mud to boulders, were left in front of the retreating
glaciers. Most of the coarser material that was deposited
on what is now the continental shelf has been transported
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G. MASSELINK AND P. RUSSELL
(wind waves with short wave periods) are known to be more
destructive than long waves (swell waves with long wave
periods). On the other hand, longer waves produce larger
run-up (e.g. Stockdon et al., 2006) and are more important for
coastal flooding. Changes to tides and tidal currents due to
climate change are expected to be minimal in the foreseeable
future, but can become significant in the long-term when
the rising sea levels start affecting the configuration of tidal
basins and estuaries. For example, a study of the response
of tides on the north-west European Continental Shelf
(Pickering et al., 2012) to a 2-m sea-level change predicts
increased tidal amplitude through much of the North Sea,
but significantly reduced amplitude in the Gulf of St Malo
and the Bristol Channel. This study also highlighted that
changes in tidal properties derived from sea-level rise can
extend to alterations in the shape of the tides and alterations
in the strength of the neap-spring cycle.
Figure 5: Map of Britain showing resistance of the geology to
denudation (Clayton and Shamoon, 1998).
onshore during the post-glacial transgression and has been
incorporated in dunes, beaches, barriers and estuaries
(Futurecoast, 2002). It is generally assumed that this
sediment source is now more or less depleted, and offshore
sediment supply to the coast by natural processes, as opposed
to beach recharge, is currently very limited. However, large
amounts of glacial material are still present on the land and
represent an important sediment source to the nearshore
system through cliff erosion (Bray, 1997). The deposition of
clay and silts onto salt marshes and tidal flats is particularly
important, because it may enable these environments to
‘keep up’ with rising sea levels (Adam, 2002).
• Waves, tides and storm surge: Coastal sediment transport
processes are mainly the result of tide- and wave-driven
currents, particularly during storm conditions. The tidal
regime, wave climate and storm surge exhibit a large spatial
variability (Figures 6 and 7) and this plays an important role
in explaining the diversity in coastal landforms in the UK
and Ireland, as well as having an effect on coastal erosion.
The potential for coastal erosion increases with wave height,
but wave period is also important, because steep waves
• Longshore sediment transport: Many beaches and barrier
systems are so-called drift-aligned systems, meaning that
their configuration, dynamics and stability are largely
controlled by longshore sediment transport processes (Orford
et al., 2002). Classic examples of such systems are spits (e.g.,
Spurn Head) and cuspate forelands (e.g. Dungeness). Even
small changes to the net littoral drift rate (or direction), for
example, due to a change in wave climate, will have major
implications for the shoreline position. Embayed beaches,
which are generally aligned according to the prevailing wave
direction are also susceptible to changes in the wave climate
and may exhibit rotation, characterised by erosion at one end
of the bay, and accretion at the other end. Annual or decadal
changes in the prevailing storm wave direction can induce
changes in the littoral drift direction over the same time
scale, which in turn can cause pronounced changes in the
beach width (De Alegria-Arzaburu et al., 2008; De AlegriaArzaburu and Masselink, 2010).
• Human impacts: Much of the coastline in the UK and
Ireland, especially that of England and Wales, is developed
(Table 1) and human activities significantly affect coastal
erosion (French, 2001). Coastal protection works such
as breakwaters, seawalls and groins are designed to halt
coastal erosion, but the resulting fragmentation of the
coast interrupts the longshore transport and exacerbates,
or even causes, downdrift erosion problems (Brown et al.,
2011). Protection of the base of eroding cliffs stops erosion,
but prevents the introduction of eroded cliff material into
the nearshore sediment system, which may also have a
deleterious effect on downdrift beaches. Land reclamation
has been very widespread in the UK (Davidson et al., 1991),
mainly in estuarine environments, but reduces the natural
resilience of these environments to sea-level rise. Coastal
defences significantly impair the ability of coastal systems
to respond naturally by restricting the free movement of
coastal sediment. Only beach nourishment (or recharge)
has a positive influence on the coastal sediment budget,
but the sediment required for recharge will have to come
from elsewhere (usually the continental shelf). The
sediment volumes required to maintain our beaches are
considerable and questions have been raised with regards to
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77
Figure 6: Map of Britain with: (a) M2 tidal amplitude (Davidson et al., 1991); (b) 10% exceedence significant wave height Hs,10%
(Draper, 1991); and (c) 1-in-50 year storm surge level (Flather, 1987).
Figure 7: Modelled seasonal means of significant wave height of swell waves for 1960–1990 (UKCP09).
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G. MASSELINK AND P. RUSSELL
78
the sustainability of this method of coastal protection. For
example, since 1995, the Sussex and Kent coast has been
nourished with 4.1M m3 of sediment, mainly gravel, at a total
cost of at least £62M (Moses et al., 2009).
• Linkages between coastal systems: Coastal evolution
and shoreline trends, especially those occuring over long
timescales (≥ 100 year), are related to process interactions
and sediment linkages between different coastal landform
units (Leafe et al., 1998; Montreuil and Bullard, 2012). An
important and useful concept arising from this notion is
that of Coastal Behavioural Systems (CBS), which attempt
to integrate coastal geomorphological units, such as cliffs,
beaches, dunes and saltmarshes that are spatially contiguous
into a single entity (Burgess et al., 2002). A CBS is generally
defined by long-term regional evolution, the widerscale interactions or drivers of change, and/or common
characteristics of shoreline features. A good example of
a CBS is the west Dorset coast. The characteristics of this
coast are a continual supply of terrestrial sediments to the
nearshore system through cliff erosion, a large net eastward
longshore sediment transport and the presence of a large
gravel beach barrier at the end of the longshore transport
corridor (Bray, 1997). Depending on the balance between
terrestrial sediment supply and marine removal, beaches
fronting the cliffs either grow or shrink, and interruptions to
the longshore drift system, for example through engineering
structures, have major implications for shoreline stability.
Clearly, the west Dorset coast is quite diverse on the small
scale, and may have alternating eroding and accreting
sections, but on the larger scale, and in the longer term, it
behaves as one unit.
Dominant types of coastal geomorphology
a. Hard-rock coasts
According to EUROSION (2004), about 42% in the UK and
56% in Ireland of the open coast (i.e. excluding estuarine
shores) is hard-rock coast, characterised by cliffs, shore
platforms and embayed beaches (Figure 8). Little is known
about the impact of climate change on hard-rock coasts, but
erosion rates are likely to increase, both as a result of more
energetic wave action at the cliff base due to rising sea level
and increased storminess, as well as increased mass-wasting
processes due to more precipitation. However, recession rates
will generally remain low, on the order of several metres over
100 years, except perhaps very locally. Quantifying erosion
rates on hard-rock coasts and increasing our understanding
of the linkages between terrestrial weathering and coastal
erosion processes remains problematic, but progress is being
made through use of advanced remote sensing techniques
that enable the collection of high-resolution data (Earlie et
al., 2013). Specifically, application of digital photogrammetry
and terrestrial laser scanning along the North Yorkshire coast
by Lim et al. (2010) has revealed that hard-rock cliff erosion
may not be as dominated by high-magnitude and lowfrequency events as hitherto thought, and that large, isolated
rockfalls are in fact part of a larger, continuous magnitudefrequency relationship.
The effect of climate change on embayed beaches is probably
more significant. These beaches are backed by cliffs or
higher ground and generally have very limited back-beach
accommodation space. They also tend to be closed systems
with no, or very limited net import of sediment due to their
embayed settings. Rising sea level will attempt to push these
beaches landward, but, with no space to move into and not
sufficient time to create new space through erosion, coastal
squeeze will result in a progressively diminishing beach
volume until no beach is left. Climate change may also result
in the rotation of embayed beaches due to changes in the wave
climate, especially the wave direction, causing alterations in
the littoral drift rate and/or direction. The narrowing and
widening of beaches at opposite ends of embayments has
been documented for several locations in the world (e.g.
Klein et al., 2002; Ranasinghe et al., 2004), and may become
significant in the south-west of England and Wales and the
Atlantic coast of Ireland where embayed beaches abound
(Jackson et al., 2005; Reeve and Li, 2009; Jackson and Cooper,
2010; Scott et al., 2011).
b. Soft-rock coasts
According to EUROSION (2004), 18% of the open coast in
the UK is soft-rock coast (only 1% in Ireland) and most of
their morphology is characterised by a beach fronting either
a cliff or non-cliffed higher ground (Figure 9). In common
with hard-rock coasts, these coasts are eroding (Lee and
Clark, 2002), but, in contrast to their hard-rock counterparts,
there is usually a significant amount of sediment present
in the coastal zone. Soft cliff retreat occurs through a
combination of marine erosion, shallow structural failures
and mass failures, and cliff height has been identified as the
principal factor controlling the failure mechanism (Quinn et
al., 2010).
Cliff erosion on soft-rock coasts is a highly episodic process
(Dong and Guzzetti, 2005) with erosion rates varying both
spatially and temporally. For example, along the Suffolk
coast, Brooks et al. (2012) carried out annual to biannual
ground survey data and applied GIS techniques to digitised
records of changing shoreline position from historical maps
and aerial photography. They revealed that the cliffs exhibited
long-term (1883–2010) recession rates of 3.5 m per year,
rising to 4.7 m per year in the period 1993–2010. The data
further revealed considerable decadal-scale variations in cliff
recession, within which are nested inter-annual fluctuations
in rates of retreat.
Brown et al. (2012) studied coastal cliff retreat and the impact
of coastal defences along the Holderness coast between
1845 and 2005. The analysis of three approximately 50-year
periods (1854–1905, 1905–1952, 1952–2005) gives a retreat
rate of between 0.8±0.4 m per year and 2.1±0.4 m per year
with retreat varying spatially and temporally due to natural
causes and human activity, especially 19th century beach
mining and coastal defence construction. In particular,
coastal defences were found to reduce sediment input and
modify the sediment budget, usually resulting in a sediment
deficit down-drift, leading to the development of a set-back.
They concluded that, at the scale of Holderness, defences
have changed the pattern of erosion rather than stopping
it, and that accelerated retreat down-drift of defences can
threaten human infrastructure and buildings and reduce the
efficiency of defences.
MCCIP Science Review 2013: 71-86
IMPACTS OF CLIMATE CHANGE ON COASTAL EROSION
79
Figure 8: Examples of hard-rock coasts: (a) plunging cliffs, Great Orme Head, Conwy, North Wales; (b) cliffs fringed by narrow
shore platform, St Bees Head, Cumbria, NW England; (c) rocky, coast with shore platform, Port Eynon, Gower, south Wales; (d)
extensive shore platform, Rhoose, Vale of Glamorgan, south Wales; (e) cliff fronted by sandy beach and shore platform, Saltburn,
Cleveland, NE England; and (f) sandy beach between cliffed headlands, Caldey Island, Pembrokeshire, south Wales (images from
Futurecoast, 2002).
Figure 9: Examples of soft-rock coasts: (a) chalk cliff fronted by shore platform, Dover, Kent, SE England; (b) cliff fronted by small
beach and shore platform, Sidmouth, Devon, south England; (c) cliff fronted by sandy beach, Burton Bradstock, Dorset, south
England; (d) Black Ven landslide complex fronted by mixed sand/gravel beach, Lyme Regis, Dorset, south England; (e) clay cliff
fronted by sandy beach and unconsolidated shore platform, Isle of Sheppey, Kent, east England; and (f) cliffs in glacial deposits
fronted by sandy beach, Holderness, Lincolnshire, east England (images from Futurecoast, 2002).
Figure 10: Examples of barrier coasts: (a) tidal flat and salt marsh, Morecombe Bay, Cumbria, NW England; (b) barrier system
fronting an estuary with extensive salt marshes, Titchwell, Norfolk, east England; (c) barrier spit stretching several km’ into the
Humber estuary, Spurn Head, Lincolnshire, east England; (d) gravel barrier with back-barrier lagoon, Slapton Sands, Devon,
south England; (e) sandy barrier with extensive dune development, Morfa Dyffryn, Gwynydd, Wales; and (f) gravel beach
capped by sandy dunes, Littlehampton, Sussex, south England (images from Futurecoast, 2002).
MCCIP Science Review 2013: 71-86
G. MASSELINK AND P. RUSSELL
80
The presence of well developed beaches along an otherwise
eroding coast is a paradox, but soft-rock coasts are generally
drift-aligned and the beaches represent the morphological
expression of the longshore transport system, rather than
stable depositional features. In fact, the source of the beach
material is cliff erosion, and the beaches would not exist were
it not for the eroding cliffs.
Walkden and Hall (2005) developed a model that considers
the cliff-platform-beach system and realistically accounts
for positive and negative feedback processes. The model was
used to model cliff retreat of single cross-shore sections on
the Naze peninsula, Essex, and it was found that a three-fold
increase in the rate of sea-level rise (from 2 to 6 mm per year)
only resulted in a 15% increase in cliff recession rate. The
model was extended by adding a one-line model to link the
different cross-shore sections and was applied to the Norfolk
coastline, where it was run for a number of climate change
and management scenarios (Dickson et al., 2007; Walkden et
al., 2008). Model output was found to be relatively insensitive
to an increase in the offshore wave height and moderately
sensitive to changes in the wave direction, but the most
important effects were due to accelerated sea-level rise. A
complex suite of responses were predicted, however, and for
some sections along the coast, the model actually predicted
shoreline progradation with increased rate of sea-level rise
owing to the delivery of sediment from eroding cliffs updrift.
Brooks and Spencer (2012) applied the SCAPE model to
the Suffolk coast and predicted that volumes of sediment
released by cliff erosion in the 21st century in response to
accelerating sea-level rise will increase by about one order of
magnitude above the sediment release estimates for the early
20th century under lower rates of sea-level rise.
The SCAPE morphodynamic model has recently been
linked to hydrodynamic, reliability and socio-economic
models by Dawson et al. (2009) to provide an integrated
analysis of coastal flooding and cliff erosion under different
scenarios of coastal management, climate and socioeconomic change, and has been applied to a 72-km stretch
of the East Anglian coastline (coastal sub cell 3b in UK
coastal management planning). The two key findings of
the modelling efforts are: (1) sediment released from cliff
erosion plays a significant role in protecting neighbouring
low-lying land from flooding; and (2) flood risk in the area
studied is expected to be an order of magnitude greater
than erosion risk. A very significant finding of this research
is that it can make economic sense to allow coastal erosion
to take place, and thereby sacrifice properties and land,
because the costs associated with the coastal erosion can be
offset by the benefits of achieving improved defence against
coastal flooding. The modelling also demonstrates that,
provided the coastal system is reasonably well understood,
some confidence can be obtained in predicting the effects of
climate change, both physically (flooding and erosion) and in
terms of socio-economics.
c. Barrier coasts
According to EUROSION (2004), 25% in the UK and 39% in
Ireland of the open coastline is backed by a (Holocene) coastal
plain, and is taken up by beaches, barriers and sandy tidal flat
systems, often capped by dunes (Figure 10). There are two
models of barrier response to rising sea level (cf. Masselink et
al., 2011). According to the Bruun rule, the shoreface profile
moves upward by the same amount as the rise in sea level,
through erosion of the upper shoreface and deposition on
the lower shoreface. According to the roll-over model, the
barrier migrates across the substrate gradient without loss
of material, through erosion of the shoreface and deposition
behind the barrier in the form of washovers and/or tidal
inlet deposits. The Bruun rule is widely used for predictive
purposes, but there is actually very limited support for its
validity and some argue it should be abandoned altogether
(Cooper and Pilkey, 2004). There is much stronger evidence
for the roll-over model, which is especially appropriate
for gravel barriers (Pye and Blott, 2006), strongly wavedominated barriers and on relatively gentle substrate slopes.
Barrier migration is not a steady process, however, but occurs
episodically when extreme water levels, often in combination
with large waves, result in overwashing of the barrier (Orford
et al., 2003). Therefore, in addition to sea-level rise, changes
in extreme water levels and storminess are also important for
the stability of barrier coasts (Pye and Blott, 2008).
The Bruun Rule and the roll-over model are essentially
two-dimensional models of shoreline response to sea-level
rise that ignore the contribution of longshore sediment
transport processes and the presence of additional sources
and sinks. Most UK barriers are drift-aligned systems and
characterised by relatively high net littoral drift rates of the
order of 104–105 m3 per year. In such settings, modifications
to the longshore transport system (e.g. due to changes in
wave climate or coastal engineering structures) can be more
important in driving coastal change than sea-level rise
(Chadwick et al., 2005). The interaction between tidal inlets
and the adjacent open coasts also requires consideration
(Burningham and French, 2006). The type of interaction will
depend on the tidal asymmetry of the inlet: when the inlet is
ebb-dominant (flood-dominant), sea-level rise may cause an
export (import) of sediment, countering (promoting) retreat
of the adjacent coast (Stive, 2004).
Recently, longer-term modelling of barrier coasts has adopted
the so-called ‘coastal-tract’ approach, which considers that
shoreline evolution over centuries to millennia must be linked
to the behaviour of the continental shelf and coastal plain
(Cowell et al., 2003a, b). In this approach, coastal evolution is
modelled using behaviour-orientated coastal change models
constrained by sediment mass conservation. The key factor
that controls the rate of coastal change is governed by the
balance between the change in sediment accommodation
space caused by sea-level rise and sediment availability. The
coastal-tract modelling approach has not yet been applied to
the UK coast.
d. Estuaries
There are 106 estuaries in Great Britain (UK, excluding
Northern Ireland) and the majority of the estuaries fall into five
groups (Figure 11; Davidson et al., 1991): (1) rias, or drowned
river valleys, are short, deep and steep-sided with small river
MCCIP Science Review 2013: 71-86
IMPACTS OF CLIMATE CHANGE ON COASTAL EROSION
81
a continuous basis, then the estuary is able to maintain its
geomorphology and reach a stable state. In the absence of
adequate supply of external sediment, some of the prominent
features such as saltmarshes and spits are likely to recede or
disappear altogether during the process of morphological
evolution against sea-level rise. The analysis also suggested
that moderate human interference in the form of dredging
and structural construction does not have a significant
impact on the overall geomorphology of estuaries in the
long-term.
Figure 11: Four main estuarine types in England and Wales
(Davidson et al., 1991).
flows; (2) coastal plain estuaries are long and funnel-shaped
with extensive intertidal zones; (3) bar-built estuaries are
short and shallow with small river flows and tidal range, and
are located along coasts with plentiful supplies of sediment;
(4) embayed estuaries are large shoreline indentations with
a relatively small amount of fresh water input; and (5) fjords
and fjards, which occur mainly in Scotland and represent
drowned glacial valleys. Estuaries interact with the adjoining
coast and can be a sediment source or sink: highly-stratified,
short and ebb-dominant estuaries (i.e. bar built estuaries) are
likely to be sediment sources, whereas partially-mixed, longer
and flood-dominant estuaries (i.e. coastal plain estuaries)
and embayed estuaries tend to be sediment sinks (Burgess
et al., 2002). Net import/export of sediments in estuarine
environments is often a very small difference between two
very large numbers. For example, Townend and Whitehead
(2003) presented a sediment budget of the Humber estuary
and found that the sediment import per tide (100 tonnes)
is only 0.08% of the total amount entering and exiting the
estuary at each tide.
Process-based models are not able to reliably predict estuarine
evolution, and conceptual, behaviour-oriented models are
more appropriate for predicting the long-term response of
estuaries to sea-level rise. Several of such models have been
applied to predict the long-term response of UK estuaries to
sea-level rise, and these have been based on estuarine rollover (Allen, 1990), tidal asymmetry (Townend and Pethick,
2002) and tidal regime theory (Pethick, 1998; Townend,
2005). Generally, these models propose that estuaries
migrate landward and upward with rising sea level through a
redistribution of sediment within the estuarine system from
outer to inner estuary, accompanied by a widening of the
tidal channels, especially in the outer estuary.
Recently, a Boolean network approach has been applied to
analyse the long-term response of estuaries to sea-level rise
(Reeve and Karunarathna, 2009). This analysis supported
the widely-kept notion that the nature of long-term
morphodynamic response to sea-level rise depends on the
type of estuary and the availability of external sediment to
meet the increasing sediment demand within the system. If
the estuary has an abundant influx of external sediment on
A more holistic approach for predicting the response of
estuaries to sea-level rise is the ASMITA model (Aggregated
Scale Morphological Interaction between Inlets and
Adjacent coast; Stive et al., 1998). This approach represents
the estuary as a series of morphological elements, such as
tidal flat, channel and ebb tidal delta. Each element evolves
towards an empirically derived equilibrium volume and
interacts with adjacent elements by sediment exchange. The
ASMITA model has been applied to several UK estuaries
and results for the Thames estuary, for example, suggest that
for the period 2000 to 2100 under accelerated sea-level rise
scenarios, the estuary will experience accretion. However,
because the accretion is predicted to be at a slower rate than
sea-level rise, intertidal profiles may be up to 0.5 m lower
with respect to high water, resulting in a deepening of the
estuary (Rossington and Spearman, 2009).
The natural response of estuaries to sea-level rise – landward
migration – is inhibited by coastal defence structures.
Erosion of the seaward edge of saltmarshes and the lower
part of the intertidal zone nevertheless occurs, resulting in a
narrowing of the intertidal zone, or coastal squeeze. The best
management solution from a geomorphological perspective
would be to relocate the line of defence landwards of its
existing position to allow salt marsh and intertidal mud
flats to develop landward of those already in existence. This
management option is referred to as managed realignment
and ideal estuaries for successful realignment schemes are
those with extensive reclaimed areas, where restoration of
the outer estuary produces the sacrificial area for sediment
erosion, and restoration of the head of the estuary will
act as a sink for these sediments allowing the estuary to
transgress (Townend and Pethick, 2002). It follows that any
restoration policy must incorporate a plan for the entire
estuary, since restoring the sink without the source, or vice
versa, would result in even greater problems of sediment
balance in the estuary than those the plan is trying to
combat. Small realignment schemes, such as are currently
being carried out (French, 2004) may be useful for habitat
generation and as scientific experiments, but are unlikely
to contribute significantly to the longer-term management
of sea-level rise in estuarine environments. In this context
the recently improved managed realignment scheme on
the Steart Peninsula, near Bridgwater in Somerset, is of
significant interest as it aims to create over 400 hectares of
valuable natural habitats including saltmarsh and freshwater
wetland, as well as providing coastal protection (http://www.
environment-agency.gov.uk/homeandleisure/floods/80793.
aspx).
MCCIP Science Review 2013: 71-86
G. MASSELINK AND P. RUSSELL
82
Adapting to coastal erosion
Humans now represent an important factor in directly
affecting coastal erosion and geomorphology, for example,
through dredging, beach nourishment and construction of
coastal defences, and also indirectly by influencing climate
and sea level (see section 1.3). At the same time, coastal
erosion has a significant impact on the human utilisation
of the coastal zone, and it is appropriate to briefly discuss
the management strategies available for coping with coastal
erosion. One of the most important concepts to have
emerged from several decades of (sustainable) coastal zone
management is that of adaptation, which, in the context
of this report, refers to an adjustment in natural or human
systems as a means of moderating the adverse impacts of and
reducing the vulnerability to coastal erosion.
There are three basic adaptation approaches: (1) protect, (2)
accommodate; and (3) retreat, and each of these approaches
may be pursued through the implementation of one of
more complementary adaptation technologies (Linham and
Nicholls, 2012; Table 2). Most of these adaptation technologies
also reduce coastal flood risk (e.g. sea dykes), and some also
contribute to habitat creation (e.g. wetland restoration). It is
noted that the three basic adaptation strategies do not quite
map onto the four policy options provided in the second
generation Shoreline Management Plans (SMPs), which
are hold the line, advance the line, managed realignment,
and no active intervention. Nevertheless, adaptation is an
important aspect of these non-statutory policy documents,
as illustrated in several case studies discussed by Pontee and
Parson (2012).
An important additional aspect of adaptation is to enhance
understanding and awareness of coastal erosion risks
through monitoring, education and policy and strategic
initiatives. An example of the latter is the Pathfinder project,
which is a £11M project funded by DEFRA to help local
authorities and communities to develop and trial methods of
coastal adaptation (http://archive.defra.gov.uk/environment/
flooding/manage/pathfinder/index.htm). Of the 15
pathfinder projects, the North Norfolk District Council
received the largest sum of money (£3M) and developed a
wide range of adaptation strategies, ranging from acquisition,
demolition and relocation of houses at risk of coastal erosion,
to improving community infrastructure (Frew, 2012).
As pointed out by Nicholls et al. (2011), it is of particular
importance to develop long-term strategic adaptation plans
for the full range of possible climate change outcomes, both in
terms of changes in sea level, extreme water level, storminess
and wave climate. An example of such long-range planning
is that being considered in the Netherlands and proposed by
the Second Delta Commission (http://www.deltacommissie.
com/en/advies). In the UK, the Thames Estuary 2100
(TE2100) Project which considers flood management in
London and its environs is a good example (http://www.
metoffice.gov.uk/services/climate-services/case-studies/
barrier). The inclusion of a 50–100 year time horizon in the
SMPs is also encouraging, but an even longer-ranging view
may be appropriate.
Table 2: Commonly applied coastal adaptation technologies.
This table has been modified from Linham and Nicholls (2012)
to make it specific to coastal erosion (the original table was
related to coastal erosion and flood management).
Adaptation approach
Technology
Hard protection
Seawall/revetments
Sea dykes
Groynes
Detached breakwaters
Land claim
Raise land areas
Soft protection
Beach nourishment
Coastal dune construction
Accommodate
Flood-proofing
Wetland restoration
Coastal aquaculture
Retreat
Managed realignment
Coastal setbacks and
zoning
The coastal management strategy (e.g. hard coastal defences,
beach nourishment, managed realignment) is also a key
aspect for determining the long-term response of the coast
to climate change effects, including sea-level rise (Dawson et
al., 2009). The second generation SMPs increasingly advise
a managed realignment policy, especially for the longer
time scale (20–50 and 50–100 years). Although managed
realignment will result in increased local erosion rates,
especially where existing coastal defences are being removed,
the enhanced erosion may benefit other sections of coast by
reducing erosion or even causing accretion. Implementation
of such strategy will have significant socio-economic
implications and is influenced by financial, conservation,
legal and social justice arguments (Cooper and McKenna,
2008; Fletcher, in press).
Conclusions
A large proportion of the coastline of the UK and Ireland
is currently suffering from erosion and 28% of the coastline
of England and Wales is experiencing erosion greater than
10 cm per year. The natural response of coastal systems to
sea-level rise is to migrate landward, through erosion of the
lower part of the nearshore profile and deposition on the
upper part, and this roll-over model is applicable to estuaries,
barriers and tidal flats. Coastal response to sea-level rise is,
however, strongly determined by site-specific factors and
usually it is these factors that determine the coastal response,
rather than a global change in sea level or a regional change
in wave climate. Any predictions of general coastal response
due to climate change are therefore rather meaningless and
will have a low confidence. However, if a detailed study is
conducted and long-term coastal change data are available,
then local or regional predictions of coastal response to
climate change can have medium confidence. The coastal
management strategy for a section of coast (e.g. hard coastal
defences, beach nourishment, managed realignment) is
also a key aspect for determining the long-term response
MCCIP Science Review 2013: 71-86
IMPACTS OF CLIMATE CHANGE ON COASTAL EROSION
of the coast to climate change effect, including sea-level
rise. Adaptation is emerging as the key coastal management
paradigm to cope with coastal erosion.
3. KNOWLEDGE GAPS
a. Long-term and large-scale coastal system response to
sea-level rise: Process-based models for open coastlines
can at best forecast coastal change over relatively short time
scales (days to a few weeks) and small spatial scales (< 1
km). There is a real need for models to be able to predict
larger scale (more than 10 km) coastal system behaviour over
longer time scales (more than ten years). Simple up-scaling of
existing process-based model does not work, and behaviouroriented or parametric models are not yet at the level to be
able to provide reliable quantitative long-range forecasts. The
Futurecoast approach of considering the coast as a series
of Coastal Behavioural Systems (CBS) is a significant step
forward, but our understanding of how these CBSs function
remains largely conceptual and this needs to be much more
quantitative. In addition, the role of coastal management will
need to be incorporated in these models. Only for soft-cliff
coastlines there is some predictive capability over long time
scales.
b. Coastal response to extreme storms: We lack the
understanding and ability to forecast the response of coastal
systems to extreme storm events. This is particularly relevant
for wave-dominated barrier coasts, where the sand and
gravel barriers serve an important natural coastal protection
role. Better understanding of and predictive tools for extreme
storm response are required to assess vulnerability of coastal
systems to extreme storm events and help identify critical
thresholds. In combination with predicted changes in sealevel, storm surge statistics and wave climate, such tools can
assist with determining coastal resilience to climate change
and assist in the design of coastal protection schemes.
c. Cliff erosional processes: On the one hand, coast cliffs
are the least complicated of all coastal systems: all cliffs
erode. However, the processes of cliff erosion, especially
the interplay between atmospheric, terrestrial and marine
processes, and the controlling role of geology, are poorly
understood, even though a reasonable amount of confidence
may be placed on the actual cliff recession rates. This lack of
understanding gets in the way of formulating reliable models
of coastal cliff response to climate change effects.
4. SOCIO-ECONOMIC IMPACTS
Coastal erosion is widespread in the UK. Current damage
due to coastal erosion is estimated at £15 million per year
which in the worst case may rise to £126 million per year
by 2080 (Foresight, 2004). Increased coastal erosion due
to climate change will provide significant opportunities
for environmental engineers (mainly coastal engineers) to
develop additional, or redesign existing, coastal protection
measures, whether in the form of hard engineering structures,
or soft engineering practices (beach recharge and managed
realignment). Increased implementation of beach recharge
schemes will have a considerable commercial effect on the
aggregate industry. Depending on how society responds to
increased coastal erosion, there can also be a very significant
83
effect on the tourist industry through the loss of beach
frontage and recreational beach area. There is now increased
realisation that against a back drop of rising sea level and
sediment management issues, current coastal management
practices, which are very much focussed on hold-the-line
adaption strategies, are not sustainable in the long-term. The
second generation Shoreline Management Plans increasingly
advocate managed realignment as an alternative adaptation
strategy, especially for less developed stretches of coast.
5. CONFIDENCE ASSESSMENT
What is already happening?
High confidence for the present statement is derived from the
detailed and comprehensive studies that have been carried
out to assess current coastal erosion rates (EUROSION,
Futurecoast and ForeSight projects).
X
What could happen?
Coastal erosion is only partly driven by sea-level rise;
therefore, medium confidence in predictions can be
achieved for many regions by assuming current erosion rates
(which are generally well-constrained) persist. However,
coastal erosion is likely to be exacerbated by sea-level rise
and coastal response is also susceptible to changes in the
wave climate (storminess and wave direction). Since there
are uncertainties about these climate-induced changes in
coastal forcing factors, and the relation between sea-level
rise and coastal erosion is highly non-linear due to the
interconnectedness of coastal systems in terms of sediment
fluxes and process linkages, high confidence for the future is
still some way off. A further complicating factor is the coastal
management, in particular the adaptation strategy used to
combat coastal erosion. Nevertheless, especially for eroding
soft-cliff coastlines, model predictions of coastal retreat are
becoming increasingly reliable and useful for coastal zone
planning and management.
X
CITATION
Please cite this document as:
Masselink, G. and Russell, P. (2013) Impacts of climate
change on coastal erosion, MCCIP Science Review 2013,
71-86, doi:10.14465/2013.arc09.071-086
MCCIP Science Review 2013: 71-86
G. MASSELINK AND P. RUSSELL
84
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